The Doctor is returned to the hospital where the doctors find he is in a self induced coma. The Brigadier takes Tardis key and has the Tardis taken to UNIT HQ along with some meteorite fragments that UNIT has found. At the nearby Auto Plastics factory (which Liz found very sinister) Ransome is being escorted to Hibbert's office by a female member of staff (Liz: What a frock! Philip: Did you spot she's an Auton? The plastic looking face is the giveaway) Ransome sees his former boss Hibbert demanding to know why he was sacked when he returned from a business trip to the USA. He is sent away, but observed by Hibbert's new partner Channing, who we saw at the hospital in the previous episode. Examining the meteorite fragment, Liz thinks it's been manufactured. Seeley hides the meteorite he has found in a box at home. A figure with a featureless face, an Auton, is tracking the signal from the sphere but looses the signal when it's put in the metal box. General Scobie comes to see the Brigadier. In the woods UNIT find a whole meteorite. Back at the hospital the Doctor is awake, steals clothes and a car belonging to the visiting doctor (played by Henry McCarthy who looks the spitting image of Roderick Spode, played by John Turner in Jeeves & Wooster) and escapes the hospital.(During this sequence, while the Doctor's in the shower Liz asks "Why does the Doctor have a tattoo?" when we see Pertwee's Dragon Tattoo, gained after a night out while he was in the Navy. I tell her that the generally accepted explanation is it's a Time Lord criminal brand). The Brigadier tries to unlock the Tardis but can't. A soldier leaves to take the meteor/Nestene energy sphere to UNIT HQ in a jeep but is ambushed by the Auton and crashes killing him. (Liz: that was bloody! Why did the Auton carry the sphere away in the box UNIT were transporting it in?) The Doctor tracks the Tardis to UNIT HQ where he tries to convince the Brigadier of his identity. The Doctor examines the meteorite fragments and wonders what was inside and where the other meteorites were collected and taken to. General Scobie visits the Auto Plastics factory to have a plastic"wax" model of him made for Madame Tussauds. While he is there Ransome breaks in, returning to his old workshop which he finds full of advanced equipment and shop window dummys. As he examines the equipment one of the dummys comes to life and advances towards him....

Another cracking episode that puts the Doctor and Unit together and introduces us to Channing, the villain of the story. The ending of the episode is overshadowed by the Autons activating sequence in part 4 but the sight of one of the dummys coming to life here is rather scary and even though you know it's coming you're never sure which of them is going to start moving! This episode has proved to be a bit of a nightmare whenever it's been released as it features a section of the Fleetwood Mac song Oh Well playing in the factory over a sequence of plastic toys being assembled. The first video version, a compilation of all four episodes, has the track removed but it was mistakenly included on the 1995 episodic release, removed again for the original DVD release and then, following a change in rights agreements, included on the Special edition version in the Mannequin Mania Box Set.

The Pertwee era is the point where location filming comes into it's own for Doctor Who. By allowing for a week's filming ahead of the studio work more frequent filming could be accomplished without eating into the actor's studio schedule or free time. Spearhead from Space has more location filming than the average story for this era but this came about by accident..... After a week's filming at Favourite Doll's Factory, Euston Road, Midland Road, Ealing Broadway, High Street & Lancaster Road, RHS Wisley (I hate Wisley, I was dragged round it too many times as a child by my garden loving father), Hatchford Park & TCC Condensors (fresh from it's appearance in The Invasion) the plan was to go into the studio to film the rest of the story. At this point the intention was to proceed to four weeks in the studio. However a this point Spearhead became the first (but not last by any means) Doctor Who story to be affected by union strike action. Pertwee then decamped to his holiday home in Ibiza. In the meantime Derrick Sherwin was at work trying to save the production and hit upon an idea. Why not film the interiors on location? So armed with 16mm cameras the team, reunited with it's star summoned home by telegram (although nowhere near as quickly as Sherwin would have liked!), ventured westwards basing themselves out of Wood Norton, a BBC facility near Evesham in Worcestshire and using Wheel Barrow Castle Cottage# & the Evesham Hotel in the area plus Madame Tussauds back in London.

Two members of the production team crop up on screen in this story, and both can be seen in this episode. The original actor playing the UNIT Commissionaire proved to be inadequate and was thrown off set with producer Derrick Sherwin, then still an Equity Card holder, taking his place. The lead Auton is played by the suspiciously sounding Ivor Orton..... who was in fact non equity card holder Assistant Script Editor Robin Squires. Initially pressed into service as an emergency stand in Squires was so good that he was used for all the main Auton appearances.